of our u.s. ambassador and three other americans. today's testimony will likely be the last for secretary of state hillary rodham clinton. after four years in office, roughly 1 million miles flown, 112 nations visited, in the past few weeks alone, she has fought illness and injury, including hospitalization. she leaves her post as the most admired woman in the world, and the gallup poll for the 11th year in a row. today, hillary clinton was under fire, and at times fired back. nbc's andrea mitchell in our washington newsroom with the story tonight. andrea, good evening. >> reporter: good evening, brian. this was hillary clinton's final testimony to congress. first in the senate, then in the house. it was not the way she wanted to end this chapter of her career. four months after the benghazi attack, committees in both chambers wanted to know what did she know and when did she know it? after a fall, a concussion and a blood clot, hillary clinton showed rare public emotion,

reflecting the toll benghazi has taken on her. >> for me, this is not just a matter of policy, it's personal. i stood next to president obama as the marines carried those flag-draped caskets off the plane at andrews. i put my arms around the mothers and fathers, the sisters and brothers, the sons and daughters and the wives left alone to raise their children. >> reporter: she said she takes responsibility for what happened. >> as i have said many times, i take responsibility, and nobody is more committed to getting this right. >> reporter: her critics were not disarmed. they wanted to know why couldn't ambassador chris stevens and three other americans be rescued. why were repeated security warnings ignored, including a cable from the ambassador on 9/11, the day of the attack, the day he was killed. >> i'm glad you're accepting responsibility. i think that ultimately, with your leaving, you accept the culpability for the worst tragedy since 9/11. and i really mean that.

had i been president at the time, and i found that you did not read the cables from benghazi, you did not read the cables from ambassador stevens, i would have relieved you from your post. i think it's inexcusable. >> reporter: pairing hostile questions all day, clinton was also the political pro. massaging big egos, sidestepping attacks when she could. when she couldn't, giving as good as she got. >> we were misled there were supposedly protests and then something sprang out of that, an assault sprang out of that. and that was easily -- ascertained that was not the fact. >> but -- >> the american people could have known that within days and they didn't know that. >> with all due respect, the fact is, we had four dead americans. was it because of a protest, or was it because of guys out for a walk one night who decided they would go kill some americans? what difference -- at this point -- does it make? it is our job to figure out what happened and do everything we can to prevent it from ever happening again, senator. >> the answers, frankly, you have given this morning are not satisfactory to me.

were you and the president made aware of the classified cable from chris stevens, that the united states consulate in benghazi could not survive a sustained assault. numerous warnings, including personally to me about the security were unanswered or unaddressed. >> reporter: she counted that congress has cut money for security. >> currently, the house has holds on bilateral security assistance, on other kinds of support for anti-terrorism assistance. so we have got to get our act together between the administration and the congress. >> reporter: after a break, the house was even tougher than the senate. >> i think when you have a united states ambassador personally warning about the situation over there, sending this cable to your office, on -- >> if i could -- 1.43 million cables a year come to the state department. they are all addressed to me. >> madam secretary, you let the consulate become a death trap.

and that's national security malpractice. >> reporter: throughout the day, the subtext for partisans on both sides, this was not the last act for hillary clinton. >> you will be sorely missed. but i for one hope not for too long. >> madam secretary, first, let me thank you for your service. and i wish you the best in your future endeavors. mostly. >> reporter: clinton returns for one last time tomorrow to introduce john kerry at his confirmation hearing to be the next secretary of state. a much happier occasion. today was so ferocious at times that one republican senator on the committee later accused clinton of faking her emotion. a sign that her critics may try to make benghazi an issue if clinton does decide to run for president, brian. >> what a day it was on capitol hill. andrea mitchell starting us off from washington. andrea, thanks. all of this brings us to our chief foreign correspondent, richard engel, in the studio. at one point the secretary just kind of waved her hand today to

indicate the whole region of the middle east as something we should have our eyes on. as you know, all too well, it's a tinder box. what do you have your eyes on right now? >> in regards to this testimony, i think she was highlighting the problems in north africa. and it really goes down to weapons. when gadhafi was falling, i was there at the time, i had never seen so many weapons in my entire life. and they were just being taken from depots, they were being handed over to militant groups. and then they went all over the region. they went from country to country and they fell into the hands of militant groups. and this is no longer theoretical. seven americans have been killed, including an ambassador in the last four months. >> it was election night last night in israel. benjamin netanyahu re-elected but by a thin margin with less power. as you have been pointing out over and over, there they sit in the middle of a lot of this. >> they feel very isolated right now. and the message in israel, and there was a lot of apathy toward this vote but the main message is, this is about your security.

you're going to vote to save your life. israel feels right now it has been surrounded by an increasingly hostile arab world. and to some degree, it's not wrong. >> richard engel, as always, good to see you. now to our other big story tonight, the secretary of defense is expected to announce tomorrow that perhaps before the end of this year, women in the u.s. armed forces may begin serving in environments like this. [ gunfire ] >> we're taking heavy fire from -- [ gunfire ] >> that video, kunar province in afghanistan in '09 was actually shot by richard engel and his team. perhaps you heard his voice there. it shows infantry combat and this will be a sea change in the u.s. military policy. we should quickly add, it's a change many women in the u.s. military have been waiting for for many years. our pentagon correspondent, jim miklaszewski on duty from there tonight.

jim, good evening. >> reporter: good evening, brian. tomorrow, defense secretary leon panetta will announce that he's lifting the ban that prevents female soldiers and marines from serving in direct combat ground combat roles. according to one senior defense official, this clears the way now for women to become combat infantry. for the past ten years, u.s. military women have served at the front lines in both iraq and afghanistan. but never allowed in direct ground combat roles. lifting the 20-year ban against women in combat will ultimately put them directly into the heat of battle. it opens some 237,000 combat-related positions to women. initially, women will be assigned to combat support roles, communications, logistics and as drivers. gradually, they'll work their way closer to battle as medics, corpsmen and manning artillery before they become combat infantry troops. despite the combat ban, women have paid the ultimate price of war.

152 u.s. military women have been killed in iraq and afghanistan. congresswoman tammy duckworth lost both her legs as an army combat helicopter pilot in iraq. she says lifting the ban will level the playing field for women. >> it's more to make it to a general, for example, without a combat arms command at the brigade or the battalion level. and this will now allow women to have those -- some of that command time. >> reporter: at first, women would have to volunteer for combat duty. and meet the same physical standards faced by men. >> well, they have to. the standard doesn't change. just because they're a woman. >> reporter: but is the military prepared for women in combat? >> there will be plenty of complaints about it. but i don't think it's going to have a negative effect on the actual strength of the force. >> reporter: and are women ready for combat? just ask tammy duckworth. >> well, i did lose my legs in a bar fight. >> reporter: at this point, it's not clear just how many women will step forward and volunteer for combat. and it's not going to happen all at once.

given the required changes in training and the regulations, actually, it could be two to three years before we see any women ready for ground combat, brian. >> jim miklaszewski at the pentagon tonight. jim, thanks. across town in washington, republicans in the house of representatives today pushed through a bill that will move the debt ceiling deadline to may, at least. while it doesn't solve it entirely, if the senate passes it, and the president signs it as expected, it will put off for now the threat of another political meltdown like the one that led to the downgrade of the u.s. credit rating back in 2011. now we go outside, which depending on where you live, might take some steeling of yourself, given the air that has descended on a lot of our country. take, for example, nbc's kevin tibbles out in the cold tonight in chicago. kevin, good evening. >> reporter: hey, why not? well, it will take a couple more frigid days to freeze the chicago river, but tonight temperatures here in chicago,

new york and elsewhere are colder than they are in juneau, alaska. [ sirens ] at one point, some 200 chicago firefighters battled a massive extra alarm warehouse fire in temperatures hovering just above zero. pouring on the water throughout the day, struggling with frozen hydrants and icy ladders. >> the stress on us, i mean, we're firefighters and we're used to dealing with the cold. >> reporter: an eerie scene of the smoldering ruins encased in ice. after a mild start to the winter in many places, this bitter cold has taken much of the nation by surprise. the coldest place in the u.s. today, a previous winner, international falls, minnesota at minus 20. but low temps gripped cities across the map. and for those working outside, time for precautions. as frostbite can set in after just ten minutes of exposure. servicing aircraft at rhode island's tf green airport, critical, bone-chilling work.

>> the key is to keep moving. once you stand still, that's when you get cold. >> reporter: nick vonek moves eggs at chicago's market. >> when it's this cold, i jut put on my snowsuit. otherwise it's just layers. >> reporter: in pennsylvania, heating companies scramble to fix broken furnaces. >> we're probably operating at 200% capacity right now. everybody is working double shifts and trying to get everybody heat. >> reporter: and in new york city, street vendors shivered but cashed in on the cold. >> hats, scarves, ear muffs, selling very well. >> reporter: as for tourists visiting the nation's capitol this inauguration week, a bit of of a shock. >> oh, my gosh, it is so cold. >> reporter: how long is it going to last? >> this unusually cold air is going to stick around into the weekend before a brief warmup early next week and then the cold air returns late next week. >> reporter: the cold is good news for northeastern ski resorts hungry for snow. but some are finding it's just too cold to open, even for

skiers. and, brian, more snow and cold in the forecast for the northeast, and midwest. i've got one other record to share with you tonight, as you shiver in new york, brian. another record was broken today in phoenix. it was over 80. >> i knew you were going to do that to us. kevin tibbles in the city that doesn't scare easily. chicago, illinois in the cold tonight. kevin, thanks. still ahead for us on a wednesday evening, a huge spike in the number of kids being diagnosed with adhd and put on meds for it. tonight, what we have learned about the reasons behind the sharp increase. later on, what aretha franklin told us today about beyonce and the uproar over lip syncing at the inauguration. ♪

as we mentioned before the break, there are new numbers out tonight that show a surge in cases of adhd in children in this country. there's also an explanation behind the spike in these numbers. we get that story from our chief medical editor, dr. nancy snyderman.

>> right here. dead center. >> reporter: christine hubner said she had never even heard of attention deficit hyperactivity disorder before her son scott was diagnosed in first grade. that was 13 years ago. >> he was very disruptive. >> i did always feel like i was getting in trouble. >> reporter: scott is now 19 and it's been a difficult journey for this mother and son. one more parents are now facing. in a new study, 843,000 children, ages 5 to 11, were followed from 2001 to 2010. the number diagnosed with adhd rose 24%. the biggest increases were in black girls and hispanic and white boys. one reason, increased awareness. adhd is usually diagnosed by a mental health professional with input from parents and teachers. typically, adhd symptoms arise in early childhood and are often mistaken for misbehavior. signs include a child easily distracted or forgetful. one who has difficulty listening, paying attention or sitting still. and a child who struggles with instructions and organization.

but what ultimately leads to a diagnosis is not just the type of behavior, but the frequency and severity. >> so it's not something that, you know, that's the child's fault or that the parent's fault. it really is a brain-based disorder. >> are you ready? >> reporter: scott and his mom are now close, after struggling with therapy, medication, frustration and guilt. >> he is very kind and nurturing, and it's just shown me what a great person he really is. ♪ >> reporter: ultimately, scott discovered his passion, music. which is helping with concentration and he is now medication-free. >> thank you. >> to find something that i can focus on was absolutely life-altering. >> reporter: he's also working to become a firefighter. and says a diagnosis of adhd doesn't have to mean a lifetime of struggle. dr. nancy snyderman, nbc news, new york. we'll take a break. and when we come back, why your boss wants you to get enough sleep.

a lot of items in the news today about our health and well-being, including the fact that facebook can full-on bum you out. german researchers call it facebook envy. it's the act of viewing all your friends' fabulous vacations, lovely children, attractive friends and great social lives. the research showed it can leave people feeling, you guessed it, lonely, frustrated and angry. this is hard to hear, but no shocker, really. a full third of us in the american work force aren't getting enough sleep to function at our peak levels as our regular viewers know all too well. the wide-awake folks at harvard say sleep deprivation costs american companies $63.2 billion a year in subpar performance. and good news and bad news on the smoking front. from the "new england journal of medicine," they state flat out, smokers lose at least one decade

of life expectancy over nonsmokers on average. the encouraging news here is quitting before 40 reduces the smoking-related death risk by 90% compared to continuing on as a smoker. well, serena williams lost it in more ways than one at the australian open, where as one sports writer put it, there are a few moments when you can physically see the changing of the guard happening. serena smashed her racket during the quarterfinal match. she was beaten by the new 19-year-old phenom, sloan stevens, after a titanic battle on the court. and aretha franklin talked with us today. she felt the urge to speak out about the beyonce lip syncing fracus after word surfaced that the version of the national anthem we heard was likely a recorded backing track. she had some thoughts on the subject as a singing veteran

herself of the last inauguration. >> when i was there in 2009, it was in the 20s. low 30s. and mother nature was not very kind to me at all. in terms of the weather. and my voice. so i could understand if she prerecorded, why she did that. >> aretha franklin telling us today, she can relate to vocal issues in the cold of washington this time of year. by the way, no official comment thus far from beyonce. when we come back, the touching story behind the photo that's been shared by millions around the world.

finally tonight, it was the shot that was shared around the world. as often happens on the web, millions of people were drawn to a photo. this one of two people in a coffee shop sharing what was clearly a private moment between the two of them. well tonight we've learned the story of dedication and devotion behind the photo. we get our report from nbc's kristen dahlgren. >> okay. you better know this one. >> g. >> reporter: it was a moment captured on a cell phone that quickly captured hearts. >> abcd, e.

>> reporter: 82-year-old john allen, patiently teaching his 70-year-old girlfriend, linda, to read again. after her stroke. >> what's this one? >> a v. >> okay. >> victory. >> right. >> reporter: almost every day, the two go to a starbucks, where john uses flash cards to quiz her on the alphabet. when fellow patron spotted them, he couldn't help but snap a picture. >> i just wanted some of my friends to see what a cool moment i had today. you know what i mean? >> reporter: but his friends shared it again and again. in almost two weeks, almost 2 million have seen it. >> wow! >> reporter: online, people explained it like this. every time i need a bit more patience, i think think of this picture. and this is what true love is all about. for a time, love was all john and linda had to hold on to. >> i couldn't even talk. except to say "i love you." >> reporter: the stroke left her barely able to speak or recognize letters. tough for a woman who five years ago was an active career woman,

a manager at raytheon. >> i want to be able to -- >> read. >> read. and i want to do the things that -- those things that i did before. >> reporter: with john's help, she may. three days a week, he also pushes her at the gym, working to restore her partially paralyzed right side. >> 16, 17, 18 -- >> reporter: even on the toughest days, she never seems to lose her smile. >> i still enjoy my life. i'm not sad. i'm not angry. >> reporter: perhaps -- >> i just love him, that's all there is to it. >> reporter: because she never lost her love. kristen dahlgren, nbc news, orange, california. >> c! >> that's our broadcast on a wednesday night. thank you for being here with us. i'm brian williams. and, of course, we hope to see you right back here tomorrow evening. good night.

right now at 6:00, one walk to school a girl will never forget. an attempted kidnapping and it appears to be caught on tape. we have the is yosurveillance v. >> the puck drops at the shark tank and it's more than about sports. hoping the team will bring business back to downtown. good evening. i'm jeff ranieri in in the weather center tracking the storm tonight. i'll let you know where the heaviest rain is falling now in a few minutes. wroo thank you for joining us, i'm raj mathai. >> and i'm jessica aguirre. live pictures from our chopper. a fire at harrison street right next to 880.

the home is in a neighborhood which is a blend. the surface streets, you see the people. so far no word on what the cause is. sometimes those homes have transients inside. at this point we're unable to tell what kind of condition the house is in and if there's anyone inside. of course we'll keep you posted. for parents it's a nightmare. new details on the attempted kidnapping of a 13-year-old girl. it happened last friday morning around 6:00. police say the girl was in east san jose near st. james and north 33rd street walking to scho school. terry mcsweepy, new to our staff, joins